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Updated: May 15, 2026
04:52
Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
A genetic polymorphism evolving in parallel in two cell compartments and in two clades.
Ward B Watt1, Richard R Hudson, Baiqing Wang
1Department of Biology, Stanford University, Stanford, CA 94305-5020, USA. wbwatt@stanford.edu
BMC Evolutionary Biology
|January 15, 2013
Summary
Genetic variation in the enzyme phosphoenolpyruvate carboxykinase (PEPCK) in Colias butterflies is unlikely to be due to neutral evolution. These PEPCK polymorphisms are likely maintained by natural selection acting in parallel across species.
Area of Science:
- Evolutionary biology
- Biochemistry
- Genetics
Background:
- Phosphoenolpyruvate carboxykinase (PEPCK) is a key enzyme linking glycolysis and the Krebs cycle.
- PEPCK exists in guanosine-nucleotide-using forms in animals and some prokaryotes.
- Natural genetic variation of PEPCK in Colias butterflies (Lepidoptera, Pieridae) was investigated.
Purpose of the Study:
- To investigate the natural genetic variation of PEPCK in Colias butterflies.
- To determine the evolutionary forces shaping PEPCK polymorphisms.
- To assess the functional impact of PEPCK variants.
Main Methods:
- Analysis of PEPCK sequence variation in two Colias species.
- Coalescent simulations to test the neutral evolution hypothesis.
- Homology-based structural modeling of PEPCK variants.
Main Results:
- PEPCK sequence exhibits high variability at both nonsynonymous and synonymous sites in common exons.
- Three major amino acid polymorphisms (Gly335↔Ser, Asp503↔Glu, Ile629↔Val) were identified and showed similar frequencies between species.
- Structural modeling indicated that these variants can alter protein function by affecting interactions.
Conclusions:
- The observed patterns of PEPCK polymorphisms are highly unlikely to be explained by neutral evolution (P ≤ 0.006).
- Evidence supports the hypothesis that these polymorphisms are maintained by parallel natural selection in Colias species.
- Further studies on the functional and fitness consequences of PEPCK genotypes are warranted.
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